Organic light-emitting display apparatus

ABSTRACT

An organic light-emitting display apparatus includes: a first substrate; an insulating layer on the first substrate; a signal wiring on the insulating layer; an organic light-emitting device on the first substrate, the organic light-emitting device defining an active area and including a first electrode, a second electrode, and an intermediate layer between the first and second electrodes; a passivation layer on the insulating layer; and a metal layer on the passivation layer at an outer region adjacent to the active area, separated from the first electrode, and contacting the second electrode and the signal wiring, wherein a first opening is in the passivation layer at the outer region, and the metal layer contacts the insulating layer at the first opening.

CROSS-REFERENCE TO RELATED APPLICATION

This application is a continuation of U.S. patent application Ser. No.14/284,355, filed May 21, 2014, which claims priority to and the benefitof Korean Patent Application No. 10-2014-0001495, filed on Jan. 6, 2014in the Korean Intellectual Property Office, the entire content of bothof which is incorporated herein by reference.

BACKGROUND

1. Field

One or more embodiments of the present invention relate to an organiclight-emitting display apparatus.

2. Description of the Related Art

An organic light-emitting display apparatus using an organiclight-emitting device has a faster response time than a liquid crystaldisplay (LCD) that is currently widely used and thus, is capable ofbetter displaying or realizing a moving image. Also, because the organiclight-emitting display apparatus is self-emitting, has a wide viewingangle, and has high luminance, the organic light-emitting displayapparatus is receiving attention as a next generation display apparatus.

The organic light-emitting device includes a pixel electrode and acounter electrode, which face each other, and an emission layerincluding an organic material disposed between the pixel electrode andthe counter electrode. The organic material is very sensitive tomoisture, oxygen, and light, and thus, when it comes into contact withany of them, a pixel shrinkage phenomenon wherein an emission region isgradually reduced in size may occur or a dark spot may be generated inthe emission region. Thus, a lifespan and/or quality of the organiclight-emitting device may be affected.

SUMMARY

One or more embodiments of the present invention relate to an organiclight-emitting display apparatus.

Additional aspects will be set forth in part in the description whichfollows and, in part, will be apparent from the description or may belearned by practice of the presented embodiments.

According to an embodiment of the present invention, an organiclight-emitting display apparatus includes: a first substrate; aninsulating layer on the first substrate; a signal wiring on theinsulating layer; an organic light-emitting device (OLED) on the firstsubstrate, the OLED defining an active area and including a firstelectrode, a second electrode, and an intermediate layer between thefirst and second electrodes; a passivation layer on the insulatinglayer; and a metal layer on the passivation layer at an outer regionadjacent to the active area, separated from the first electrode, andcontacting the second electrode and the signal wiring, wherein a firstopening is in the passivation layer at the outer region, and the metallayer contacts the insulating layer at the first opening.

The first opening may extend across the passivation layer, and thepassivation layer may include two portions separated at the firstopening.

The metal layer may have a second opening outside the second electrode.

The metal layer may have a plurality of the second openings.

The plurality of the second openings may be arranged along a lineparallel to an end of the second electrode.

The plurality of the second openings may be arranged at an interval.

The second openings may be configured to allow impurities in thepassivation layer to pass therethrough.

The metal layer may include a same material as that of the firstelectrode.

The organic light-emitting display apparatus may further include apixel-defining film covering a part of the first electrode and a part ofthe metal layer and contacting the passivation layer, wherein the firstopening may be outside the pixel-defining film.

The second electrode may be electrically coupled to the signal wiringthrough the metal layer.

A circuit unit may be below the passivation layer.

The first opening may prevent impurities in the passivation layeroutside the active area from migrating to the active area.

The organic light-emitting display apparatus may further include: asecond substrate on the second electrode; and a sealant between thefirst and second substrates and coupling the first and secondsubstrates.

BRIEF DESCRIPTION OF THE DRAWINGS

These and/or other aspects will become apparent and more readilyappreciated from the following description of example embodiments, takenin conjunction with the accompanying drawings in which:

FIG. 1 is a plan view schematically illustrating a part of an organiclight-emitting display apparatus according to an embodiment of thepresent invention;

FIG. 2 is a cross-sectional view taken along the line II-II′ of FIG. 1;and

FIG. 3 is a plan view of the region P1 of FIG. 2.

DETAILED DESCRIPTION

Reference will now be made in detail to embodiments, examples of whichare illustrated in the accompanying drawings. In this regard, thepresent embodiments may have different forms and should not be construedas being limited to the descriptions set forth herein. Accordingly, theembodiments are merely described below, by referring to the figures, toexplain aspects of the present description.

In the drawings, like reference numerals refer to like elementsthroughout and overlapping descriptions may not be repeated.

While terms, such as “first”, “second”, etc., may be used to describevarious components, such components must not be limited to the aboveterms. The above terms are used only to distinguish one component fromanother.

An expression used in the singular encompasses the expression of theplural, unless it has a clearly different meaning in the context.

In the present specification, it is to be understood that the terms suchas “including,” “comprising,” or “having,” etc., are intended toindicate the existence of the features or components and are notintended to preclude the possibility that one or more other features orcomponents may also exist or may be added.

It will be understood that when a component or layer is referred to asbeing “on” another component or layer, the component or layer can bedirectly on the other component or layer or intervening component orlayers may also be present.

In the drawings, for convenience of description, sizes and/orthicknesses of components or layers may be exaggerated for clarity. Forexample, because sizes and/or thicknesses of components or layers indrawings are arbitrarily shown for convenience of description, the sizesand thicknesses are not limited thereto.

Expressions such as “at least one of,” when preceding a list ofelements, modify the entire list of elements and do not modify theindividual elements of the list. Further, the use of “may” whendescribing embodiments of the present invention relates to “one or moreembodiments of the present invention.”

Hereinafter, one or more embodiments of the present invention will bedescribed in detail with reference to accompanying drawings.

FIG. 1 is a plan view schematically illustrating a part of an organiclight-emitting display apparatus 1 according to an embodiment of thepresent invention, FIG. 2 is a cross-sectional view taken along the lineII-II′ of FIG. 1, and FIG. 3 is a plan view of the region P1 of FIG. 2.

Referring to FIGS. 1 and 2, the organic light-emitting display apparatus1 according to an embodiment of the present invention includes a firstsubstrate 101, an insulating layer 20 formed on the first substrate 101,a signal wiring 300 formed on the insulating layer 20, an organiclight-emitting device OLED for defining an active area AA on the firstsubstrate 101, a passivation layer 208 formed on the insulating layer20, and a metal layer 400 formed on the passivation layer 208 at anouter region outside of (e.g., adjacent to) the active area AA.

The first substrate 101 may be a flexible substrate and may be formed ofplastic having excellent thermal resistance and excellent durability.However, the first substrate 101 is not limited thereto and may beformed of any one of various materials, such as metal or glass.

The organic light-emitting device OLED defines the active area AA of thefirst substrate 101 and is electrically coupled (e.g., electricallyconnected) to a thin-film transistor TFT. A pad unit 10 may be disposedaround the active area AA so as to transmit an electric signal from apower supply device or a signal generating apparatus to the active areaAA.

An internal structure of the organic light-emitting display apparatus 1will now be described in further detail with reference to FIG. 2.

The insulating layer 20 may be formed on the first substrate 101. Theinsulating layer 20 may include a buffer layer 201, a gate insulatingfilm 203, and an interlayer insulating film 205.

The buffer layer 201 may be formed directly on the first substrate 101.The buffer layer 201 may be formed on an entire surface of the firstsubstrate 101 (e.g., at the active area AA and at the outer region). Thebuffer layer 201 may be formed of any material capable of preventingimpure elements from penetrating through the first substrate 101 andproviding a flat surface on the first substrate 101.

The thin-film transistor TFT may be formed on the buffer layer 201. Thethin-film transistor TFT may include an active layer 202, a gateelectrode 204, a source electrode 206, and a drain electrode 207.

The active layer 202 may be formed of an inorganic semiconductor, suchas amorphous silicon or polysilicon, an organic semiconductor, or anoxide semiconductor and may include a source region, a drain region, anda channel region.

The gate insulating film 203 is formed on the active layer 202. The gateinsulating film 203 may be formed to correspond to (e.g., may be formedon) the entire first substrate 101. For example, the gate insulatingfilm 203 may be formed to correspond to the active area AA and the outerregion of the first substrate 101. The gate insulating film 203 is usedto insulate the active layer 202 and the gate electrode 204 from eachother and may be formed of an organic material or an inorganic material,such as SiN_(x) or SiO₂.

The gate electrode 204 is formed on the gate insulating film 203. Thegate electrode 204 may include gold (Au), silver (Ag), copper (Cu),nickel (Ni), platinum (Pt), palladium (Pd), aluminum (Al), or molybdenum(Mo), or may include an alloy, such as aluminum:neodymium (Al:Nd) ormolybdenum:tungsten (Mo:W), but is not limited thereto and may be formedof any suitable material considering design conditions.

The interlayer insulating film 205 is formed on the gate electrode 204.The interlayer insulating film 205 may be formed to correspond to anentire surface of the first substrate 101. For example, the interlayerinsulating film 205 may be formed to correspond to the active area AAand the outer region.

The interlayer insulating film 205 is disposed between the gateelectrode 204 and the source electrode 206 and between the gateelectrode 204 and the drain electrode 207 to insulate them and may beformed of an inorganic material, such as SiN_(x) or SiO₂.

The signal wiring 300 may be formed on the insulating layer 20. Thesignal wiring 300 may be formed on the interlayer insulating film 205.The signal wiring 300 may be formed at the outer region. The signalwiring 300 may be electrically coupled to a second electrode 215 tosupply a signal to the second electrode 215. The signal wiring 300 maybe a cathode power supply line ELVSS. When the signal wiring 300 is thecathode power supply line ELVSS, the cathode power supply line ELVSS maybe coupled to (e.g., connected to) a cathode power source having (e.g.,supplying) a lower voltage than a common power supply voltage; forexample, the cathode power supply line ELVSS may be a ground voltage ora negative (−) voltage. The signal wiring 300 may be formed of the samematerial as the source or drain electrode 206 or 207 and may be formedduring the same act or process.

The source and drain electrodes 206 and 207 are formed on the interlayerinsulating film 205. For example, the interlayer insulating film 205 andthe gate insulating film 203 are formed to expose the source and drainregions of the active layer 202, and the source and drain electrodes 206and 207 are formed to contact the exposed source and drain regions ofthe active layer 202.

The thin-film transistor TFT of FIG. 2 is a top-gate transistorsequentially including the active layer 202, the gate electrode 204, andthe source and drain electrodes 206 and 207, but alternatively, the gateelectrode 204 may be disposed below the active layer 202.

The thin-film transistor TFT is electrically coupled to the organiclight-emitting device OLED to drive the organic light-emitting deviceOLED and is covered and protected by the passivation layer 208.

The passivation layer 208 may be an organic insulating film. Impuritiesmay be generated in and/or may be present in the passivation layer 208.The impurities may be, for example, remaining moisture generated duringoperations (e.g., during manufacture).

The passivation layer 208 may be formed on the insulating layer 20. Thepassivation layer 208 may be formed on the interlayer insulating film205. The passivation layer 208 may cover a part of the signal wiring300.

A first opening H1 (e.g., a first hole) may be formed in the passivationlayer 208. The first opening H1 may be formed at the outer region. Thefirst opening H1 may have a valley shape. By forming the first openingH1, impurities generated in and/or present in the passivation layer 208formed outside the first opening H1 or generated in and/or present inthe passivation layer 208 formed at the outer region (e.g., a portion ofthe passivation layer 208 at a side of the first opening H1 opposite tothe active area AA) may be prevented from being transmitted to (e.g.,from migrating to) the active area AA. Accordingly, a pixel shrinkagephenomenon may be prevented, thereby increasing a lifespan andreliability of the organic light-emitting display apparatus 1.

The metal layer 400 may be formed on the passivation layer 208. Themetal layer 400 may contact the second electrode 215. The metal layer400 may contact the signal wiring 300. When the metal layer 400 contactsthe signal wiring 300, the second electrode 215 and the signal wiring300 may be electrically coupled to each other. The metal layer 400 maybe formed of the same material as a first electrode 211 and during thesame act or process.

The metal layer 400 may contact the insulating layer 20 through thefirst opening H1. The metal layer 400 may contact the interlayerinsulating film 205 through the first opening H1. Accordingly, thepassivation layer 208 may be separated (e.g., separated into twoportions) by the first opening H1 (e.g., the first opening H1 may extendacross the entire passivation layer 208).

A second opening H2 (e.g., a second hole) may be formed in the metallayer 400. The second opening H2 may be formed outside the secondelectrode 215. A plurality of second openings H2 may be formed. Theimpurities generated in the passivation layer 208 below the metal layer400 are discharged through (e.g., emitted through) the second opening H2and thus, are prevented from being transmitted into (e.g., migrating to)the active area AA. Accordingly, a pixel shrinkage phenomenon is reducedor prevented, thereby increasing the lifespan and reliability of theorganic light-emitting display apparatus 1.

The organic light-emitting device OLED is formed on the passivationlayer 208, and the organic light-emitting device OLED may include thefirst electrode 211, an intermediate layer 214, and the second electrode215.

The first electrode 211 is formed on the passivation layer 208. Forexample, the passivation layer 208 does not cover the entire drainelectrode 207 but exposes a region (e.g., a predetermined region) of thedrain electrode 207, and the first electrode 211 may be formed to becoupled (e.g., connected) to the exposed region of the drain electrode207.

In the current embodiment, the first electrode 211 may be a reflectiveelectrode.

The second electrode 215, disposed to face the first electrode 211, maybe a transparent or semi-transparent electrode.

Accordingly, the second electrode 215 may allow light emitted from anorganic emission layer included in the intermediate layer 214 topenetrate therethrough. For example, the light emitted from the organicemission layer may be reflected at or by the first electrode 211 that isa reflective electrode and be transmitted towards the second electrode215 or may be directly discharged or emitted towards the secondelectrode 215.

However, the organic light-emitting display apparatus 1 according to thecurrent embodiment is not limited to a top emission apparatus but may bea bottom emission apparatus wherein the light emitted from the organicemission layer is discharged or emitted towards the first substrate 101.In this case, the first electrode 211 may be a transparent orsemi-transparent electrode, and the second electrode 215 may be areflective electrode. Alternatively, the organic light-emitting displayapparatus 1 may be a dual emission apparatus wherein the light isdischarged or emitted in two directions, towards both front and rearsurfaces thereof.

A pixel-defining film 213 is formed of an insulating material and on thefirst electrode 211.

The pixel-defining film 213 may cover a part of the metal layer 400. Thepixel-defining film 213 may cover a part of the first electrode 211. Thefirst opening H1, formed in the passivation layer 208, may be formedoutside the pixel-defining film 213. The pixel-defining film 213 maycontact the passivation layer 208 therebelow. In this embodiment, thepixel-defining film 213 may contact the passivation layer 208 formed ata side of the first opening H1 closer to the active area AA.Accordingly, the impurities generated in and/or present in thepassivation layer 208 formed outside the first opening H1 (e.g., at aportion of the passivation layer 208 at a side of the first opening H1opposite to the active area AA) may be prevented from being transmittedto (e.g., migrating to) the active area AA through the pixel-definingfilm 213.

The second electrode 215 may be electrically coupled to the signalwiring 300 through the metal layer 400.

The pixel-defining film 213 exposes a region (e.g., a predeterminedregion) of the first electrode 211, and the intermediate layer 214 isdisposed on the exposed region of the first electrode 211.

The intermediate layer 214 includes the organic emission layer.Alternatively, the intermediate layer 214 may include the organicemission layer and may further include at least one of a hole injectionlayer (HIL), a hole transport layer (HTL), an electron transport layer(ETL), and/or an electron injection layer (EIL). However, the currentembodiment is not limited thereto, and the intermediate layer 214 mayinclude the organic emission layer and may further include other variousfunctional layers.

A built-in circuit unit 600 may be formed below the passivation layer208. The built-in circuit unit 600 may be formed at the outer region.The built-in circuit unit 600 may be formed of a plurality of thin-filmtransistors TFT.

A second substrate 102 is disposed on or above the second electrode 215.The second substrate 102 may be a flexible substrate and may be formedof plastic having excellent thermal resistance and excellent durability.However, the second substrate 102 may be formed of any of variousmaterials, such as metal or glass.

A sealant 500 is disposed between the first and second substrates 101and 102 (e.g., the sealant 500 may extend between corresponding portionsof the first and second substrates 101 and 102). The sealant 500 may beformed on the insulating layer 20. The sealant 500 couples (e.g.,combines) the first and second substrates 101 and 102 to each other. Thesealant 500 may be formed at the outer region. The sealant 500 mayinclude frit. The sealant 500 operates as a shielding film (e.g., animportant shielding film) for preventing an organic material of theorganic light-emitting device OLED from being deformed due toimpurities, such as external oxygen and moisture.

The first opening H1 and the second opening H2 will now be described infurther detail with reference to FIG. 3.

Referring to FIG. 3, the metal layer 400 may be formed on thepassivation layer 208. The second opening H2 may be formed in the metallayer 400. The second opening H2 may be formed outside an end line CE ofthe second electrode 215. In this embodiment, the plurality of secondopenings H2 may be formed (e.g., the plurality of second openings may bearranged parallel to the end line CE and may be arranged at aninterval). When the second opening H2 is formed, the impuritiesgenerated in and/or present in the passivation layer 208 may bedischarged through (e.g., emitted through) the second opening H2.Accordingly, the impurities may be prevented from being transmitted tothe active area AA, thereby increasing the lifespan of the organiclight-emitting display apparatus 1.

The first opening H1 may be formed in the passivation layer 208. Thefirst opening H1 may have a valley shape. The passivation layer 208 mayhave a structure separated by the first opening H1 (e.g., thepassivation layer 208 may be two portions thereof separated by the firstopening H1), and the impurities generated in the passivation layer 208outside the first opening H1 are prevented from penetrating into theorganic light-emitting device OLED along or through the pixel-definingfilm 213 due to the separated structure, thereby increasing the lifespanof the organic light-emitting display apparatus 1. Also, because themetal layer 400 and the insulating layer 20 contact each other at thefirst opening H1, the passivation layer 208 may have a further sealedand/or separated structure.

As described above, according to one or more of the above embodiments ofthe present invention, a pixel shrinkage phenomenon may be prevented,thereby increasing a lifespan and reliability of an organiclight-emitting display apparatus.

While one or more embodiments of the present invention have beendescribed with reference to the figures, it will be understood by thoseof ordinary skill in the art that various changes in form and detailsmay be made therein without departing from the spirit and scope of thepresent invention as defined by the following claims and theirequivalents.

What is claimed is:
 1. An organic light-emitting display apparatuscomprising: a first substrate; an insulating layer on the firstsubstrate; a signal wiring on the insulating layer; an organiclight-emitting device on the first substrate, the organic light-emittingdevice defining an active area and comprising a first electrode, asecond electrode, and an intermediate layer between the first and secondelectrodes; a passivation layer on the insulating layer; a circuit unitbelow the passivation layer and comprising a plurality of thin-filmtransistors; and a metal layer on the passivation layer at an outerregion adjacent to the active area and contacting the second electrodeand the signal wiring, wherein a first opening is in the passivationlayer at the outer region, and the metal layer contacts the insulatinglayer at the first opening, wherein the metal layer has a second openingabove the passivation layer and outside the second electrode, andwherein the first opening is formed toward the active area from thecircuit unit and the second opening is formed toward the outer regionfrom the circuit unit.
 2. The organic light-emitting display apparatusof claim 1, wherein the metal layer is separated from the firstelectrode.
 3. The organic light-emitting display apparatus of claim 1,wherein the pixel defining film covers a part of the first electrode anda part of the metal layer and contacts the passivation layer.
 4. Theorganic light-emitting display apparatus of claim 1, wherein the firstopening extends across the passivation layer, and wherein thepassivation layer comprises two portions separated at the first opening.5. The organic light-emitting display apparatus of claim 1, wherein themetal layer has a plurality of the second openings.
 6. The organiclight-emitting display apparatus of claim 5, wherein the plurality ofthe second openings are arranged along a line parallel to an end of thesecond electrode.
 7. The organic light-emitting display apparatus ofclaim 1, wherein the first opening is configured to prevent impuritiesin the passivation layer at the outer region from migrating to theactive area.
 8. The organic light-emitting display apparatus of claim 1,further comprising: a second substrate over the second electrode; and asealant between the first and second substrates and coupling the firstand second substrates to each other.